Last week Vladimir Putin, the Russian president, repeated his denial that the Kremlin had intervened in the election.

“Watch my lips, no. All those things are fictional, illusory and provocations, lies,” he said at an international forum,” he said.

“All these are used for domestic American political agendas. The anti-Russian card is played by different political forces inside the United States to trade on that and consolidate their positions inside.”

Last month James Comey, the FBI’s director, confirmed that the Bureau had launched a criminal investigation into allegations of collusion between Russia and the Trump campaign.